Italy’s Interior Minister Matteo Salvini on Wednesday denounced a judge who freed the German captain of a charity rescue ship accused of forcing an Italian naval blockade. Salvini suggested the ruling was politically motivated.

Judge Alessandra Vella freed Carola Rackete from house arrest on Tuesday, saying that by bringing migrants to port in defiance of the Italian Navy, she was looking to save lives. “Take off your [judge’s] robes and become a candidate for the left if you want to get into politics,” Salvini said on Facebook.

The national magistrates association warned that Salvini was undermining the judiciary’s independence, Reuters reports.

Salvini last month introduced rules effectively closing ports to rescue ships.